Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4b52d3a67b9f099…

MALICIOUS

PDF

96.6 KB Created: 2021-08-20 03:51:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5a01305e61f11124eadb40ee4eb55212 SHA-1: 93269aa02925548a4c0f9e463bfafedf02b5f48a SHA-256: b4b52d3a67b9f09939f14b6b8a25866fd1ac6cc462f79e8b1ae5a01d0185a845
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external links, many pointing to compromised WordPress sites. These links likely serve as a link farm to redirect users to malicious content, such as phishing pages or malware downloads. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/c03c1abfc7b1275a4d75794c86c8ee18/votakefi.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/34dclpm3ul24iqpbo5gthdneib/35445484070.pdf
    • https://resulgame.com/calisma2/files/uploads/34859631730.pdf
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202106191622013262.pdf
    • https://peterdegendt.be/file/pamudeseronibunet.pdf
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/3f384937f442dbde884137665da258ff/gugowegi.pdf
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1607472b4615c8---15991842765.pdf
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/8a35c9567671b90c717afd327ef0b807/77084914368.pdf
    • http://plovdivweek.com/app/templates/js/ckfinder/userfiles/files/5743906700.pdf
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a36bb089efc---77265576622.pdf
    • https://obermeyer-modemarkt.de/upload/file/69296859946.pdf
    • http://bularz-auto.pl/images/userfiles/file/gibitekobanuxumowel.pdf
    • http://babywagen24.de/userfiles/file/60740620267.pdf
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c116f006f6d---nuzozobameveto.pdf
    • http://royalgroup.at/tmp/15890819684.pdf
    • https://ip-kamera-rendszer.hu/ckfinder/userfiles/files/83430805906.pdf
    • http://rencontres-icare.org/userfiles/file/7837691348.pdf
    • http://bugaboo-buffalo.eu/UserFiles/File/dadowivutijekusikiwujur.pdf
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d70689596ae---85991954543.pdf
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609dd9521f9c5---36161279354.pdf
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/7eh7b14dr0bdtvalrfvs04j3dk/xubedefomanodetexuf.pdf
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/92126d496647b52490235c2ef2ee03b6/43120242050.pdf
    • http://kassa.pl/userfiles/file/jupoxemazovazilulugi.pdf
    • https://projetovm.com/uploads/files/96759645696.pdf
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/t28eoqbmjcvi5lagtascuirm3j/dudajelijinuz.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=the+season+of+divorce+john+cheever+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001169c.bin
fc1e8a114ebeb59bcaab33b9760fe596f38c38debecfff2685acd48e08f276f3
pdf-font-stream PDF embedded font (sfnt) at offset 0x1169C 16936 bytes
font_01_sfnt_off000142ed.bin
82830a361361102d3b1af6f7ea2fa51aca5c39841bb7aa66589e878b156c705f
pdf-font-stream PDF embedded font (sfnt) at offset 0x142ED 10732 bytes
font_02_sfnt_off00015b81.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15B81 16792 bytes